The present invention concerns the general technical field of electrical household food preparation appliances such as particularly multifunction household food processors or even blenders provided more particularly for the preparation of liquids. The present invention relates to a vessel provided with a removable closing lid comprising hinge means for articulating the lid the on the vessel.
Such a vessel is particularly intended to be associated with a household food processor in which food products are finely divided, mixed and/or emulsified by an appropriate tool fixed to a shaft that projects from the center of the bottom of the vessel and is driven by an electric motor. It is thus necessary that the lid suitably cover the vessel in order to prevent the food products from leaving the vessel during the course of processing. It is also necessary that the opening and the closing of the lid be easy to perform and that the lid not be in the way during removal of the food products from the vessel.
There are known particularly in the prior art household food processors in which the lid is locked onto the vessel or onto the housing of the appliance by means of jaws. Such appliances have a high fabrication cost. There are equally known food processors in which the lid is locked onto the vessel by means of a bayonet closure. This manner of closing is however not easy to use.
There has already been proposed in the document U.S. Pat. No. 4,111,372 a household food processor in which a hinge is formed by a tenon extending from the lid, engaged in a longitudinal cut-out of the vessel. Insertion of the tenon into the cut-out is not easy to perform and requires good eyesight and a certain dexterity. In addition, this manner of connection presents sealing problems.
The document EP 0556467 relates to a food processor of which the lid is articulated on the vessel by a hinge, while the document EP 0812560 discloses an arm articulated to the outside of the vessel to which a lid is connected in a removable manner, requiring the fabrication of two separate parts.
One can note that there exist articulated lids, lids connected in a removable fashion to the vessel of the food processor, a lid connected in a removable manner to an articulation arm. In contrast, one does not find a lid that is at the same time articulated and connected in a removable manner to the vessel, assuring an easy placement and a reliable and easily controllable closing of the lid on the vessel, using a minimum of parts reducing at the same time the number and duration of operation for assembling the appliance.
The object of the present invention is to provide a solution permitting use of the appliance to be simplified, while reducing the number of parts to be fabricated and consequently also reducing the time for assembling the appliance.
To this end, the present invention has for its object a working enclosure for an electrical household food preparation appliance comprising a vessel and a lid, the vessel and the lid having articulation means, wherein said articulation means have two complementary nesting surfaces, one integral with the lid and the other integral with the vessel, presenting along at least one pivot axis a series of at least partially circular sections perpendicular to said pivot axis. The advantage of this invention resides in the fact that the complementary nesting surfaces permit at the same time connecting the lid in a removable manner while permitting it to be articulated to the vessel. The at least partially circular sections can form a circle or even one or several arcs of a circle, or even envelop the above-cited forms in the case of undulating, ribbed or embossed surfaces.
According to a preferred version of the invention, the complementary nesting surfaces are respectively male and female, or in other terms, convex and concave, for example semicylindrical or even hemispherical, such a conception permitting the construction of the lid and of the vessel, as well as their cleaning, to be facilitated. The male and female surfaces can arbitrarily belong to the lid or the vessel.
Forms of construction relating to an alternative version can however be envisioned, such as articulation means formed on the vessel as on the lid by coaxial disks of the same diameter, spaced apart and connected to their immediate neighbors by a wall covering one quarter to their periphery.
According to a preferred embodiment of the preferred version of the invention, the female nesting surface is formed by a concave surface extending at most over an angle of substantially 180xc2x0. Such a design of the complementary male and female nesting surfaces permits removal and replacement of the lid in a very simple and reliable manner without favoring one particular direction for placement or withdrawal. It also permits a good guiding of the lid along the circular path with respect to the vessel.
Preferably, said concave nesting surface is integral with the vessel, at least a portion of this surface being situated above a plane parallel to the upper edge of said vessel and passing through the center of curvature of said concave surface, alternatively, said concave nesting surface is integral with said lid, at least a portion of this surface being situated below a plane parallel to the upper edge of said vessel and passing through the center of curvature of said concave surface. This arrangement permits retention of the lid during a translation along the axis of the vessel.
According to a preferred form of the invention, the complementary nesting surfaces are hemispherical surfaces. Due to this arrangement, the lid can be articulated about a multitude of axes converging at the center of the spherical nesting surfaces.
According to another embodiment, the male nesting surface has a free end provided to be engaged along the pivot axis against the female nesting surface. This arrangement equally permits obtaining a lid that is removable from the vessel while assuring a guiding during rotation of the lid. The concave surface can then extend over more that 180xc2x0.
Advantageously, the male or female nesting surface integral with the lid is situated at the end of an arm that projects toward the outside. This arrangement permits the articulation surfaces to be easily visible. Thus, if these surface are not nested in one another, the lid lifts during the engagement of the locking means located substantially opposite, indicating to the user that the lid is not correctly closed.
Preferably, the male or female nesting surface integral with the vessel is arranged on a handle of the vessel. On the one hand, this arrangement permits the articulation means to be extended toward the outside, on the other hand, this complementary nesting surface can be constituted by an appropriate shaping of a portion of a handle and can thus be integrated therewith.
According to a particularly advantageous form of the invention, the lid has an inner or outer annular nesting surface, extending perpendicular to the plane formed by the edge of the lid adjacent to the edge of the vessel and dimensioned to be nested at the inside or the outside of the opening of the vessel, the dimension of this surface perpendicular to said plane formed by the edge of the lid being smaller in its part opposed to the articulation means, or in its part closest to the articulation means. Due to this or these annular nesting surfaces, the lid is guided with respect to the opening of the vessel. This arrangement is useful particularly when the male and female nesting surfaces of the articulation means are formed by convex and concave hemispherical surfaces permitting the lid to be caused to pivot around a multitude of convergent axes.
According to a variant of the preceding characteristic, preferably, the lower edge of the annular nesting surface has at least one recess while the inner wall of said vessel has at least one positioning projection disposed to come to engage with said recess when the lid is in position for closing the vessel. This arrangement permits the positioning role of the annular nesting surface, integral with a lid, to be improved.
The present invention equally has for its object an electrical household appliance for food preparation having a housing forming a base for receiving a vessel closed by a lid, the vessel and the lid having articulation means, locking means to maintain the lid in its closing position on the vessel being provided on the housing in order to cooperate with a locking surface of the lid, by the fact that the vessel and lid form a working enclosure in accordance with the preceding arrangements.
Advantageously, then, the articulation means have a concave nesting surface integral with the vessel, or with the lid, at least a portion of this surface being located above, or below, a plane passing through the center of curvature O of said concave surface and through the bearing point of the locking means on the locking surface of the lid when said locking means lock the articulated lid on the vessel in the closed position. This arrangement permits a locking at two points to be obtained.
Advantageously also the locking means come to bear on the lid in a region diametrically opposed to the articulation means, this arrangement permitting an effective locking to be obtained at only two points, the locking means and the articulation means.
Advantageously also, the locking means come to bear on the top of the lid, this arrangement permitting the design of the appliance to be simplified.